This invention relates to vaporizers and will have special but not limited application to a device and method for vaporizing fluids for use in foundry binder systems.
Most foundry binder systems are generally referred to as "cold box" systems, which means that the sand mold or core is hardened primarily by inducing a chemical reactant or catalyst upon resin treated sand. many of these cold box systems are currently available on the market and several of the most favored systems utilize methyl formate, methylal, or other liquids as a reactant or curing agent for the resin binders. Due to the speed of cure, it is necessary to first form the sand mold or core in the presence of the resins and then add the curing agent to affect hardening. Premature addition of the curing agent will often ruin the mold or core by causing the mold to harden before it is formed into the desired shape. Addition of the curing agent in its non-gaseous state to the mold or core is also undesired as this often produces imcomplete hardening of the mold.
It is for these reasons that vaporizing (or gassing) units have been developed which heat the curing agent to its boiling point and then deliver the gaseous agent selectively to the sand mold or core which has been formed. Heretofore, these machines have utilized heat vaporization techniques which are sometimes potentially dangerous and often inefficient due to the inability to properly regulate the heat throughout the container which holds the curing agent.